Kun-Won Jang

A Study on Design and Implementation of the Ubiquitous Computing Environment-based Dynamic Smart On/Off-line Learner Tracking System

In order to provide a tailored education for learners within the ubiquitous environment, it is critical to undertake an analysis of the learning activities of learners. For this purpose, SCORM (Sharable Contents Object Reference Model), IMS LD (Instructional Management System Learning Design) and other standards provide learning design support functions, such as, progress checks. However, in order to apply these types of standards, contents packaging is required, and due to the complicated standard dimensions, the facilitation level is lower than the work volume when developing the contents and this requires additional work when revision becomes necessary. In addition, since the learning results are managed by the server there is the problem of the OS being unable to save data when the network is cut off. In this study, a system is realized to manage the actions of learners through the event interception of a web-browser by using event hooking. Through this technique, all HTML- based contents can be facilitated again without additional work and saving and analysis of learning results are available to improve the problems following the application of standards. Furthermore, the ubiquitous learning environment can be supported by tracking down learning results when the network is cut off.

Design of Secure Dynamic Clustering Algorithm using SNEP and μTESLA in Sensor network

Contrary to general network, sensor network has many restrictions such as energy recharge. Accordingly, security mechanism used to general network cannot be applied to sensor network. Many researchers propose method of security and energy efficiency separately. To maximize energy efficiency, the methods to support data aggregation and clusterhead selection algorithm are proposed. To strengthen the security, the methods to support encryption techniques and manage a secret key that is applicable to sensor network are proposed. However, energy and security issues are trade-off. This paper is devoted to design secure routing protocol combining conventional routing protocol with security protocol. This new protocol is that encryption algorithm and key management method are applied to specific routing protocol.

M-commerce model by enhanced location privacy protocol in GSM

Today, e-commerce transactions continue to impact the global business environment profoundly and its technologies and applications are beginning to focus more on mobile computing and the wireless Web. As the usage of mobile devices becomes pervasive and convenient, the e-commerce through mobile devices is an emerging field. However, most of e-commerce systems do not only support privacy rights for user but also the rights for the merchant provider. A collection and processing of personal data may lead to private and family life violation, thus discouraging the public against the usage of new technologies. In this paper, we propose the enhanced-privacy m-commerce schemes, which are based on the e-commerce model using the GSM user authentication protocol.

Design of the Covered Address Generation using the Super Increasing Sequence in Wireless Networks

The General security method of wireless network provides a confidentiality of communication contents based on the cryptographic stability against a malicious host. However, this method exposes the logical and physical addresses of both sender and receiver, so transmission volume and identification of both may be exposed although concealing that content. Covered address scheme that this paper proposes generates an address to which knapsack problem using super increasing sequence is applied, and replaces the addresses of sender and receiver with addresses from super increasing sequence. Also, proposed method changes frequently secret addresses, so a malicious user cannot watch a target system or try to attack the specific host. Proposed method also changes continuously a host address that attacker takes aim at. Accordingly, an attacker who tries to use DDoS attack cannot decide the specific target system.

Implementation of New Active Service to Support Ubiquitous Card for U-City

This system proposes ubiquitous card service which is to give us the unique personalized information in UCity( Ubiquitous City). The user have to submit the personal information(considered ones intellectual powers, concerns, and age etc.) in U-Card(Secure Smart Card with PKI and RF tag) with secure channel to the information servers, and the user acquired the unique information that is created by system with the user¿s personal information. This system can keep individual information and apply U-Card having public key and certificate to the protection of the invasion of one¿s privacy and support the communication between RFID and Reader. So the system acquires the personalized information then provide services(customized information about the contents) on the base of U-City.

Design and Verification of Security API Structure Based on PKCS #11

This paper is devoted to design SecurityAPI that solves the disadvantages and restrictions due to several attack types of public key SecurityAPI and provides the security services. SecurityAPI may be applied to both domestic and foreign standard using domestic standard algorithm such as KCDSA and HAS-160 added to conventional PKCS #11. To verify the security of SecurityAPI for protecting key object based on public key, we provide the flow chart of each SecurityAPI function by graphical method using CPN and describe the process of SecurityAPI by sentence. Also, we analyze the CPN model of proposed Security API structure using the place invariant and verify the security of SecurityAPI that we do not need the modification for input data.